Zn(NO_3)_2-Leu-H_2O体系(25℃)的相平衡及新相配合物的合成与性质

Synthesis, Properties and Phase Equilibrium of Zn(NO_3)_2-Leu-H_2O System(25 ℃)

用半微量相平衡方法研究了硝酸锌 -亮氨酸 -水体系在 2 5℃及全浓度范围内的溶度性质 ,绘制了体系的相图和饱和溶液折光率曲线 ,发现并制备了未见报道的非一致溶解配合物 [Zn( Leu) ( NO3 ) 2 ( H2 O) ]· H2 O( A)和 Zn( Leu) 2 ( NO3 ) 2 · H2 O( B) ,通过化学分析、元素分析、 IR和 TG-DTG等对其组成、结构及热稳定性进行了研究 .用精密转动弹热量计测定配合物的标准燃烧能分别为 ( -1 2 6 92 .80± 5 .83)和 ( -1 5 34 5 .71±9.1 1 ) J/ g,求得它们的标准燃烧焓分别为 ( -4 5 2 3.2 2± 2 .0 8)和 ( -72 0 8.86± 4 .2 8) k J/ mol,标准生成焓分别为 ( -6 1 5 .6 7± 2 .2 7)和 ( -1 86 3.1 6± 4 .6 0 ) k J/

The solubility of Zn(NO 3) 2-Leu-H 2O system at 25 ℃ in the entire concentration range has been investigated by phase equilibrium method. The corresponding phase diagram and refractive index diagram have been constructed. The incongruently soluble complexes [Zn(Leu)(NO 3) 2(H 2O)]·H 2O(A) and \{Zn(Leu) 2(NO 3) 2·H 2O(B)\} which have not been reported in literature, have been prepared. The compounds are characterized by IR spectra, TG-DTG, as well as chemical and elemental analyses. The constant volume combustion energies of the complexes, Δ cE(complex, s), have been determined by a precision rotating bomb calorimeter at 298.15 K. The standard enthalpies of combustion, Δ cH θ m(complex, s), and standard enthalpies of formation, Δ fH θ m(complex, s), are calculated for the complexes.